WO 2005/076149 discloses a hand-held device (sometimes referred to as a mobile deixis device) having a camera to capture an image of an object. The hand-held device further includes a wireless communication device coupled to the camera and to a wireless network to communicate the image to a computer having a database. In the computer, a web database is created having images of known objects, wherein the associated text which describes features of the object in the image typically includes geographical location information of the object. Using the hand-held device, an image-based query can be formed simply by pointing with the camera and snapping a photo. The image is used to find matching images of the same location. In an embodiment, the mobile deixis device includes a global positioning system receiver to identify the geographical location of the mobile communication device to help eliminate non-useful images. In an alternative embodiment, a GPS co-ordinate-based query to retrieve from a web site such as www.mapquest.com a map covering the surrounding area can be obtained, and used to refine further the results of the image-based search.
An image-based search generally requires a high level of data processing power to perform the actual image matching, which is therefore generally not carried out in a mobile device. This in turn requires the communication of the captured image data to a remote data processor like the computer, so that a wireless connection with a relatively high bandwidth is also required.